The ADT7476A is a dBCOOL controller that can monitor up to five voltages, control and monitor up to four fans, and has high and low frequency fan drive signals. It has an on-chip temperature sensor, two remote temperature sensors, a temperature measurement range of up to 191°C, an automatic fan speed control mode that controls system cooling based on the measured temperature, an enhanced acoustic mode that significantly reduces user perception of changing fan speeds, a thermal protection feature via the THERM output, monitoring of the performance impact of the Intel® Pentium® 4 processor, a thermal control circuit via the THERM input, support for 3-wire and 4-wire fan speed measurement, and limit comparison of all monitored values. All TACH and PWM channels support 5V, and meet the SMBus 2.0 electrical specifications.
This handbook describes the ADT7476A dBCOOL remote thermal controller and voltage monitor. It outlines the device’s ability to monitor up to five voltages, control up to four fans, and measure temperature with both on‑chip and remote sensors, supporting an extended temperature range up to 191 °C.
The document includes functional block diagrams, pin configuration tables, electrical specifications, absolute maximum ratings, thermal characteristics, and detailed programming instructions for fan speed control, temperature measurement, and SMBus communication.
| Supply Voltage | 3.0 V – 3.6 V |
|---|---|
| Supply Current (ADC active) | 1.5 mA – 3 mA |
| Local Sensor Accuracy | +0.5 °C |
| Temperature Resolution | 0.25 °C |
| TACH Input High Voltage | 2.0 V |
| Maximum Voltage on +12 V in Pin | 16 V |
| Maximum Junction Temperature | 150 °C |
| Input Current at Any Pin | 5 mA |
The device operates from 3.0 V to 3.6 V supply voltage.
It can control and monitor up to four fans.
The controller can measure temperatures up to 191 °C.
The THERM pin offers thermal protection and can be used as a bidirectional temperature input or output.